fifteen. years i in the OIE of the ee Cypr @a. 
Miscellanies. : 379 
mensions at Maria Island, is still more degraded at the Island of 
Decres and Josephine, is only a miserable abortion on the rocks of 
Nuytland, and is no longer visible at port King George. The same 
‘thing is observable in the Phasianellus ; 3 their proper habitation is at 
Maria island where vessels are loaded with them ; and after suffering 
insensible degradations they are Jost at port King George. It is in- 
teresting to witness the same phenomena, exhibited in a horizontal 
direction on the present surface of the earth, appearing again in a 
vertical direction upon the different surfaces, which, at successive 
periods have limited” the exterior configurations of the terrestrial 
&, 
globe.—Bib. Univ. Dec. 1830. 
Be Monograpiy of the genus: aera ---Daméril and De Blain- 
ville made a report to the Academy on the 27th of December, on 
the memoir of M. Ducxos, entitled Monographie du genré Cyprea, 
(vulgairement- coquilles porcelaines.) 'This kind of shells is one of 
those for which amateurs have still a predilection, not only on ac-_ 
count of the elegant and singular form of the shell, but especially 
from, the beauty of their robes, the almost infinite variety of the col- 
ors with which they are ornamented, and of the splendid kind of 
varnish with which: they are covered: It is in this. genus therefore, 
as well as the cones and volutes, that are included those species 
Which have retained the greatest venal value. It is time that this _ 
genus, which has long been only an object of luxury and curiosi- 
ty, should rise to a level with the other departments of conchology. 
This was not an easy thing, on account of the connection between , 
the animal and its shell, and of the peculiar developement of the 
lobes of its mantle, which, void.in its éarliest period, acquires a 
_ Successive ‘developement, so as to cover the entire shell when the _ 
animal is at rest. 'The shell passes through three or four distinct 
stages, which are very different in form, and especially so in struc- 
ture, thickness and color. Several naturalists, with a view to an ex- 
planation of the fact, that in the.same species there are found both 
dwarfs and giants, have thought it sufficient to state’that the animal 
changed its shell, an opinion which appears’to the reporters to have 
been victoriously refuted. ‘The labors of Lamarck, de Blainville, 
and of Gray, adjunct curator-of the British Museum, have still left 
much to be desired. -M. Duclos has been perseveringly eo 
